Prevalence of bronchoconstriction induced by eucapnic voluntary hyperpnoea in recreationally active individuals

Exercise-induced bronchoconstriction (EIB) is more prevalent in elite athletes than in the general population. Many of these athletes provide a positive eucapnic voluntary hyperpnoea (EVH) challenge without previous diagnosis of EIB. It is unknown whether this is specific to elite athletes or whether the same risk applies to recreationally active individuals. The purpose of this study was to investigate the prevalence of a positive EVH challenge in a population of recreationally active individuals.

136 recreationally active individuals (Age: 21.9 ± 3.7 years; Height: 175 ± 9 cm; Weight: 70.9 ± 10.0 kg) without previous history of asthma or EIB, volunteered to take part in the study. All participants completed an EVH challenge, which was deemed positive if FEV1 fell ≥10% from baseline at two consecutive time points, and was reversible following inhalation of a short acting β2-agonist.

18 of 136 (13.2%) participants had a positive EVH challenge. Of the 18 individuals, the fall in FEV1 from baseline ranged from -12% to -50%. At baseline, percentage predicted FEV1 (97.5 ± 12.5% versus 104.9 ± 10%; p < 0.01), FEV1/FVC ratio (79.5 ± 6.9% versus 87.8 ± 5.5%; p < 0.01), FEF25-75 (3.73 ± 1.00 versus 4.73 ± 1.00 l/s; p < 0.01) and predicted PEF (89.4 ± 8.8% versus 97.5 ± 13.6%; p < 0.05) values for EVH positive participants were significantly lower than EVH negative participants respectively.

Overall, 13.2% of recreationally active individuals with no previous history of asthma presented with a positive EVH challenge. Individuals who are recreationally active may benefit from an objective bronchial provocation challenge, given that self-reported symptoms alone only provide a supportive role towards a valid EIB diagnosis.